Portion of a watch



FIG. 1 is a front and right side perspective view of a portion of a watch showing our new design;

FIG. 2 is a front and left side perspective view thereof;

FIG. 3 is a front elevation thereof;

FIG. 4 is a right side view thereof; and,

FIG. 5 is a left side view thereof.

The broken line showing of various regions of the watch is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a portion of a watch, as shown and described. 